I agree with JT.
If you really want to go down this route, I would go with option 1 since the OC is low on funds.
I have done option 2 but only in an OC that had plenty of funds and it was purely about getting a contractor or goods on-site as quickly and simply as possible and I could be confident of getting the money reimbursed promptly, backed up by a paper trail showing the expense was approved.
With option 1, the owner(s) could pay money against their levy accounts. They would then be in advance of their levy payments. The OC should issue them with an account statement showing the payment received and that their account is in credit. The OC would have cash and could spend it on tree surgery or anything else the committee approves consistent with the budget or urgently necessary work.
When the next levy is due, those whose account balances are in credit would either not need to pay anything or would not need to pay as much, thereby, in effect, getting their money back.